1. Field of the Invention
This present invention generally relates to a solar energy collection system for a pitched roof covered with roofing plates, with joist elements that can be laid in the ridge-eaves direction, which joist elements can be laid overlapping one another in the ridge-eaves direction, whereby plate-shaped modules having cells are located on the joist elements butted up against one another or adjacent to neighboring roof covering plates, the length of which modules can be greater than the greatest coverage length of a roofing plate, and the width of which can be greater than the system coverage width of the roofing plate.
2. Background Information
Such a system is described in German Patent No. 94 09 453.9 U1, for example. In this system, modules are arranged so that they overlap one another in the longitudinal direction of the roof. In this specification, the longitudinal direction is called the ridge-eaves line, and the transverse direction is designated a line parallel to the ridge or to the eaves. As the joist elements, there are wooden profiles laid in the ridge-eaves direction which, on their ridge-side end, are in contact with a roof batten and on their eaves-side end are in contact with a wooden batten that is laid parallel to a roof batten and adjacent to the latter. The wooden batten projects beyond the upper edge of the roof batten by approximately the thickness of the module. The wooden profiles, on their surface, have a depression that runs in the longitudinal center, so that this depression, when located on the edges of two modules butted against one other, serves as a drain channel for the discharge of any water that may have penetrated into the gap. One disadvantage of this system is that additional wooden battens must be laid parallel to the roof battens, and that additional stays that are engaged around the eaves-side edge of the modules are necessary for fastening.
A energy collection system for a pitched roof covered with roofing plates is described in EP-A-0 549 560. The system has frame-like joist elements that can be laid overlapping in the ridge-eaves direction. A plate-shaped module having cells can be inserted into each joist element, whereby the length of the module is greater than the greatest coverage length of a roofing plate, and the width of which is greater than the system coverage width of a roofing plate.
The lateral longitudinal edges of a joist element are realized in the conventional manner for a roofing plate in the form of water channels or bottom baffles and cover channels or top baffles. In this manner, joist elements and roofing plates can be laid in a row parallel to the eaves so that a joist element, with its lateral longitudinal edge which is realized in the form of a cover channel, always covers the lateral longitudinal edge of the neighboring joist element or of the neighboring roofing plate which is realized in the form of a water channel. On the system of the known art, it is not possible to install the modules with butt joints.
FR-A-2 354 430 describes a module that has an eaves-side segment with solar cells and a ridge-side segment that does not have any solar cells. The modules can be laid so that they overlap one another in the ridge-eaves direction, whereby a module is in contact with its ridge-side segment directly on a roof batten that runs in the direction parallel to the ridge, and is covered by the ridge-side segment with the solar cells of the higher module in the ridge-eaves direction. With the ridge-side segment, each module is supported on the segment that does not have the solar cells on the lower module in the ridge-eaves direction. The modules are not fixed to the roof batten on the ridge side, so that on each roof batten there is a hook that is engaged around the ridge-side each of a roof batten and the ridge-side edge of an overlapped module. The hook is inserted between the overlapping modules and is engaged around the eaves-side edge of the overlapping module. In this manner, the hook prevents the displacement of the overlapping module toward the eaves.